What are the most common symptoms of hypothyroidism? how is it diagnosed?

Since hypothyroidism is caused by a deficiency of the thyroid hormone ,the severity of symptoms would depend on the degree of deficiency .Common complaints are weight gain with a puffy face ,hoarseness ,dry skin, thinning of hair and changes in the nails ,along with an increased sensitivity to cold.It is diagnosed by checking the level of thyroid hormones and imaging studies if indicated.